Centos system modify time zone

I created a file when I was working on the operating system today. I found that the time and local time were not correct when I checked the ls. After I checked the date, I found that the time zone is EDT (Eastern Daylight Timing). The time zone is rarely modified once in a hundred years. It is almost the least commonly used operation (except for the great gods who operate and maintain the NTP server). Record it.

[ root@dbback ~]# date
Mon Mar 2701:26:48 EDT 2017

One, set the time zone of the Centos system

Enter the command: tzselect
Input in sequence: 5)Asia → 9)china → 1)east China —BeiJing…. → 1)Yes

[ root@dbback ~]# tzselect 
Please identify a location so that time zone rules can be set correctly.
Please select a continent or ocean.1) Africa
 2) Americas
 3) Antarctica
 4) Arctic Ocean
 5) Asia
 6) Atlantic Ocean
 7) Australia
 8) Europe
 9) Indian Ocean
10) Pacific Ocean
11) none - I want to specify the time zone using the Posix TZ format.
#?5
Please select a country.1) Afghanistan		  18) Israel		    35) Palestine
 2) Armenia		  19) Japan		    36) Philippines
 3) Azerbaijan		  20) Jordan		    37) Qatar
 4) Bahrain		  21) Kazakhstan	    38) Russia
 5) Bangladesh		  22)Korea(North)39) Saudi Arabia
 6) Bhutan		  23)Korea(South)40) Singapore
 7) Brunei		  24) Kuwait		    41) Sri Lanka
 8) Cambodia		  25) Kyrgyzstan	    42) Syria
 9) China		  26) Laos		    43) Taiwan
10) Cyprus		  27) Lebanon		    44) Tajikistan
11) East Timor		  28) Macau		    45) Thailand
12) Georgia		  29) Malaysia		    46) Turkmenistan
13) Chinese Hong Kong		  30) Mongolia		    47) United Arab Emirates
14) India		  31)Myanmar(Burma)48) Uzbekistan
15) Indonesia		  32) Nepal		    49) Vietnam
16) Iran		  33) Oman		    50) Yemen
17) Iraq		  34) Pakistan
#?9
Please select one of the following time zone regions.1) Beijing Time
2) Xinjiang Time
#?1
 
The following information has been given:
 
	China
	Beijing Time
 
Therefore TZ='Asia/Shanghai' will be used.
Local time is now:	Mon Mar 2711:38:02 CST 2017.
Universal Time is now:	Mon Mar 2703:38:02 UTC 2017.
Is the above information OK?1) Yes
2) No
#?1
 
You can make this change permanent for yourself by appending the line
	TZ='Asia/Shanghai';export TZ
to the file '.profile'in your home directory; then log out and log in again.
 
Here is that TZ value again,this time on standard output so that you
can use the /usr/bin/tzselect command in shell scripts:
Asia/Shanghai

Second, replace the Centos system time zone file

[ root@dbback ~]# date
Sun Mar 2623:38:13 EDT 2017[root@dbback ~]#  cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime    #Choose Asia when you set the Chinese time zone/Shanghai
cp: overwrite ‘/etc/localtime’? yes

Check the Centos system time after setting

[ root@dbback ~]# date
Mon Mar 2711:38:43 CST 2017